Doors increasingly have devices which are operated by means of electrical energy for improving safety or convenience.
To supply them with energy, these devices are either galvanically connected, for example, by way of sliding contacts or by way of flexible cables, to an external energy source, or they have energy stores themselves, for example, to rechargeable cells or batteries.
The first-mentioned case has the disadvantage that sliding contacts are susceptible to faults and cable connections significantly impair visual appearance. In the second case, the necessity for separate stores increases operating costs. The space required by the stores also impairs functionality and visual appearance.
DE 10 2004 017 341 A1 describes a hinge plate with a built-in transformer for contactless energy transmission. This hinge plate comprises a primary coil disposed in a frame hinge plate part and a secondary coil disposed in a leaf or sash hinge plate part. A hinge plate pin passing through the two coils serves to magnetically couple the secondary coil to the primary coil, which are spaced apart from each other in the direction of the hinge axis.
Although the contactless energy transmission from a fixed frame into a leaf or sash disposed pivotably on the frame is in principle desirable to avoid the aforementioned disadvantages, tests have shown that, with the hinge plate described in DE 10 2004 017 341 A1, only very small levels of electrical power can be transmitted from the primary side to the secondary side since the power loss in the transmission is very high.